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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Acetylcholinesterase and simple esterases distribution in squirrel monkey brain, examining activity in neuropil and postrema area neurons
L-dihydroxyphenylalanine intraperitoneal injection effect on S-adenosylmethionine concentration in rat brain
Balloon-borne monkeys possible brain damage due to cosmic rays, discussing thindown tracks and acute vasculitis
Component connection schemes of brain for trainable feedback flight control system
Model describing symmetrical information processing along visual pathways of brain
Cerebellum substrate for memory list processing in brain assuming Perceptron mechanism
Cutaneous blood flow in anesthetized pig forelimb modified by brain temperature changes
Oxidative and hydrolytic enzymes localization in rhesus monkey brain, investigating glutaraldehyde fixation effect with histochemistry
Brain norepinephrine synthesis pharmacological inhibition, discussing effects of ovariectomy to decrease sensitivity
L-dopa multiinjection timed effects on rat brain norepinephrine metabolites concentrations, observing zero time control rated modifications
Brain monoamines localization and metabolism and endocrine function, discussing pituitary secretion and neurotransmitter input
A study was made of 32 monkeys which survived one to seven years after total body exposure to protons or to high-energy X rays. Among these 32 monkeys there were 21 which survived two years or longer after exposure to 200 to 800 rad. Glioblastoma multiforme developed in 3 of the 10 monkeys surviving three to five years after receiving 600 or 800 rad 55-MeV protons. Thus, the incidence of tumor development in the present series was far higher than the incidence of spontaneously developing brain tumors in monkeys cited in the literature. This suggests that the tumors in the present series may have been radiation-induced.
Two neurological disorders, cerebral palsy, and traumatic brain damage as from an accident, are considered. The discussion covers the incidence of disabilities, their characteristics, and what is now being done to deal with them, particularly in reference to areas in which the capabilities of the engineer can be effectively applied.
The results of investigations of the physiological role of serotonin (5-Ht) in the brain are discussed. Experiments are described in detail and results presented in tabular and graphical form.
Albino rats were kept for a year under conditions of daily motor load or constant hypokinesia. An increase in motor activity results in a rise in the acetylcholinesterase activity determined in the synaptosomal and purified mitochondrial fractions while hypokinesia induces a pronounced decrease in this enzyme activity. The butyrylcholinesterase activity somewhat decreases in the synaptosomal fraction after hypokinesia but does not change under the motor load pattern. Motor load causes an increase in the amount of synaptosomal water-soluble proteins possessing an intermediate electrophoretic mobility and seem to correspond to the brain-specific protein 14-3-2. In the synaptosomal fraction the amount of membrane proteins with a low electrophoretic mobility and with the cholinesterase activity rises. Hypokinesia, on the contrary, decreases the amount of these membrane proteins.
Proposed brain-surgery tool has an octogonal fixture for positioning latex tube over incision. Eight stainless-steel wires embedded in latex extend to hold positioning fixture. Another eight are also embedded in the latex. Concentric sleeves are successively inserted into expandable latex tube. The first sleeve is placed over a solid rod. Last sleeve is a stainless-steel tube 1 inch in diameter. It is overcoated with Teflon (or equivalent) material.
Three experiments are described in which tracking difficulty is varied in the presence of a covert tone discrimination task. Event related brain potentials (ERPs) elicited by the tones are employed as an index of the resource demands of tracking. The ERP measure reflected the control order variation, and this variable was thereby assumed to compete for perceptual/central processing resources. A fine-grained analysis of the results suggested that the primary demands of second order tracking involve the central processing operations of maintaining a more complex internal model of the dynamic system, rather than the perceptual demands of higher derivative perception. Experiment 3 varied tracking bandwidth in random input tracking, and the ERP was unaffected. Bandwidth was then inferred to compete for response-related processing resources that are independent of the ERP.